You can spend Ox Credits on any 'Buy Now' transaction. It is not possible to use Credits when you make an offer.
Using Ox Credits for an order
When you reach the final step of the checkout, where you select your payment method, any available credits will be automatically applied. You can apply a maximum of 100 Ox Credits per order, and to use credits there is a minimum order value of 150 SGD to use credits. You can choose to apply a smaller amount in case you want to save some of your credits for a future transaction.
It is not possible to redeem Ox Credits for cash.